Dental crown or plate swaging device.



PATENTED SEPT. 19, 1905.

J. A3311). DENTAL GROWN 0R PLATBSWAGING DEVICE.

APPLIOATION FILED FEB. 5, 1904.

Fig.1. 7

UNITED STATES PATENT oEEIoE.

JOSEPH A. REID, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY MESNE ASSIGNMENTS, TO CENTURY DENTAL INSTRUMENT COMPANY.

DENTAL CROWN O R PLATE SWAGING DEVICE.

Specification of Letters Patent.

Patented Sept. 19, 1905.

Application filed February 5 1904. Serial No. 192,248.

To all whom it may concern:

Be it known that I, J OSEPI-I A. REID, a citizen of the United States, residing at San Fran cisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Dental Crown or Plate Swaging Devices, of which the following is a specification.

My invention relates to an improved swaging device for swaging dental crowns or plates, the object of my invention being to provide an apparatus of this character by means of which plates can be swaged with greater accuracy than heretofore, also with greater economy of time.

Afurther object of the invention is to provide an apparatus by'means of which plates can be swaged equally well over either a metal or plastic die.

My invention, therefore, resides in the novel construction, combination, and arrangement of parts for the above ends, hereinafter fully specified and particularly pointed out in the claims.

In the accompanying drawing, Figure 1 is a side elevation of my improved apparatus. Fig. 2 is a vertical section thereof. Figs. 3 and 4 are views similar to Figs. 1 and 2 of a modified form of the apparatus. Fig. 5 is a detail perspective view of the lever for operating the screws.

Referring to the drawings, 1 represents a suitable base, which is secured to a table or standard, preferably by means of screws or bolts 2, through holes 3, provided in the baseplate for that purpose. Around the circumference of said plate are arranged a' number, preferably three, of standards 4, screwthreaded at each end, the lower ends being screwed into the base-plate, while the threads on the upper ends are adapted to be passed through holes 5 in a cap 6. This cap rests upon shoulders 7 formed upon the standards 4:. It is firmly secured thereon by means of nuts 8, screwed upon the ends of the standards. The height of the shoulders is sufficient to allow the swaging device to he slid underneath into position between two of the standards without removing the nuts and the cap. Said swaging device comprises a cylindrical shell 9, in which fits snugly the lower cupshaped mold-section 10. The upper cupshaped mold-section 11 also fits snugly within the shell and has a central guide or passage 12 for a plunger 18. The plunger 13 is threaded at its upper portion and is screwed into an' outer tubular screw 14, the latter again being screwed within the central boss or hub 15 of the cap 6. Suitable holes are provided in the heads of these screws for the insertion of the end of a lever 16, the bent end 17 being applied in the hole 18 of the outer screw and the straight end being passed through the hole 19, extending through the head of the inner screw.

The manner of using the device is as follows: The cap 6 having been placed in position and the screws thereon, the lower moldsection is first filled with soft modeling compound 20, in which is set the die 21, upon which the plate is to be swaged. This is then inserted in the cylindrical shell or ring 9 and pushed down into place. Then a piece of sheet-lead 22 of about one-sixteenth to oneeighth of an inch in thickness and of suflicient area to cover the die is placed upon it. Then paraifin 23 in small pieces, or in any other preferred form is placed upon the sheet of lead of sufficient extent to fill thecavity in the two mold-sections. Then the upper mold-section is placed in position. The double screws are already in position, and the outer screw is first turned, so as to force the upper mold -section down upon the lower section as far as it can be forced. Then the inner screw is screwed upward or outward. This leaves a small empty space in the mold-cavity,and then by reapplying screw pressure to the outer screw and forcing said screw down again upward into the cavity left by the inner screw,

thus allowing the two mold-sections to be brought tightly together. When this has been done, the apparatus is ready for compression of the lead, and this is efiected by again screwing the inner screw down, exerting an enormous pressure upon the parafiin, and squeezing thelead down uponthe die, forming a counter-die therefrom. The screws are now unscrewed, the shell and contents are removed, and the sections are separated, the lead counter-die and the paraffin coming off with the upper mold section and the die remaining in the lower section. The apparatus is now ready for the final step of swaging the gold plate. For this purpose the gold plate is laid upon the die. A sheet venting'it coming in contact with the lead of thin paper is then laid over the gold, pre- The upper mold-section is then laid upon the lowermold-sectiomand the process of compression is now repeated, the effect being to bend or swage the gold plate accurately between the die and the counter-die.

Instead of the apparatus shown in Figs. 1 and 2 I may also use a modification shown in Fig. 3. In this modification the cylindrical shell or ring is dispensed With, and instead of said shell and the base and standards there are provided the press-sections 24 25, which are bolted together by bolts 26, forming a chamber in which the die, the lead plate, and the paraffin are placed in the same way as before. Through the hub of the upper press-section 24 is screwed the outer screw, and thisis first screwed down, its lower portion 27 being smooth to act as a piston to compress the paraffin, and then when the outer screw has'been screwed to asufiicientextentpressureis applied to the inner screw to screw the same-still farther, obtainingagreater pressure per square inch and obtaining an enormous pressure upon the paraffin, thereby forming the lead counterdie into shape. The apparatus shown in this modification is cheaper and has certain advantages, but is not so convenient for manipulating as that shown in the first modification.

A very important feature of my invention consists of the use of the lead plate to form the counter-die. Heretofore paraffin, soap, and other plastic substances have been used to swage the dental plate upon the die; but they have all been defective in this respect, that they do not offer sufficient resistance to the tops of ridges or projections formed upon the dental plate. By the use of paraffin it is not possible to force the plate into the form of the rugii or fine lines of the mouth to the extent which is possible with soft metal. When a thick metal counter-die is used, the counter-die becomes swaged around the dental plate, so that when it is removed it is not possible to separate the dental plate from the counter-die except by springing the same, which ruins the dental plate. By using a thin sheet of soft metal the soft metal can be peeled off the dental plate without changing its form. By applying force resembling that of the hydraulic press to the paraffin to force the sheet metal into position there are obtained all the advantages consequent upon the use of a thick metal counter-die, while at the same time the ready removal of the dental plate is permitted.

The same apparatus can be used for dental crowns, using a reduced matrix for swaging the crown.

The advantage of using the double screw is that the device does not have to be taken apart to refill. The large screw fills the chamber with parafiin by driving the paraffin from between the molds. By making the lower portion of the screw'blank or smooth the paraflin is prevented working into the threads. vAnother advantage of the above construction is that the e'fiect-of forcing the molds together in practicing the invention is to reduce the sizeof the .swagingchamber,

- and this results in a better efiect in proportionto the pressure applied.

I claim 1. In an apparatus of the character described, in combination with the upper and lower mold-sections and the die therein, a thin sheet of soft metal, placed over the metal plate to be swaged upon said die, and means for forcing the sheet down upon the die, said means comprising plastic material within the upper mold-section, and aplunger for forcing down said plastic material, substantially as described.

2. In an apparatus of the character described, in combination witha shell, the upper and lower mold-sections therein, the die, the thin sheet of soft metal shaped over the die to form a connter-die,.the plastic material in the upper mold-section, and means for applying pressure to said plastic material, substantially as described.

3. In an apparatus of the character described, the combination of the frame, the upper and lower mold-sections, the outer screw bearing upon the upper section to forcethe mold-sections together, plastic material within the sections, and an inner screw working within the outer screw and having a smooth lower end fitting snugly within the lower portion of said outer screw and acting as a plunger upon the plastic material, substantially as described.

4. In an apparatus of the character described, the combination of upper and lower mold sections, means comprising a hollow screw for forcing said mold-sections together, plastic material within the sections and a device reciprocating within the screw and having a snug bearing to act as a plunger upon the plastic material, substantially as described.

5. In an apparatus of the character described, the combination of a cylinclricalframe, upper and lower mold-sections therein,ascrew bearing upon the upper section to force the two sections together, plastic material within the sections,and a device working within the screw and having a snug bearing therein to act as a plunger upon the plastic material, substantially as described.

6. In an apparatus of the character clescribed, the combination of upper and lower mold-sections, a frame supporting the lower mold-section, a screw screwed into said frame and bearing upon the upper section to force the mold-sections together, plastic material within the sections,.and a device having asnug bearing in the screw and moving independently thereof to act as a plunger upon the plastic material, substantially as described.

WWW

7. In an apparatus of the character described, the combination of means for forming a mold-cavity, a support for said means, provided with means for preventing the escape of plastic material from said mold-cavity, a screw having an operative engagement with said support whereby said cavity can be enlarged or diminished by the turning of said screw, plastic material within the cavity, and a device moving independently of the screw to act as a plunger upon the plastic material, substantially as described.

8. In an apparatus ofv the character described,the combination of acylindrical frame,

hand in the presence of two subscribing witnesses.

J. A. REID.

Witnessesr F. M. WRIGHT, BESSIE GORFINKEL. 

